/*
 *  Google Analytics
 ** 只在生产模式的客户端中使用
 */
export default ({
  app
}) => {
  /*
   ** Only run on client-side and only in production mode
   */
  if (process.env.NODE_ENV !== 'production') return
  /*
   ** Include Google Analytics Script
   */
  (function (i, s, o, g, r, a, m) {
    i['GoogleAnalyticsObject'] = r;
    i[r] = i[r] || function () {
      (i[r].q = i[r].q || []).push(arguments)
    }, i[r].l = 1 * new Date();
    a = s.createElement(o),
      m = s.getElementsByTagName(o)[0];
    a.async = 1;
    a.src = g;
    m.parentNode.insertBefore(a, m)
  })(window, document, 'script', 'https://www.google-analytics.com/analytics.js', 'ga');
  /*
   ** Set the current page
   */
  ga('create', 'UA-163998158-1', 'auto')
  /*
   ** Every time the route changes (fired on initialization too)
   */
  app.router.afterEach((to, from) => {
    /*
     ** We tell Google Analytics to add a `pageview`
     */
    ga('set', 'page', to.fullPath)
    ga('send', 'pageview')
  })
}
